Getting plenty of work on special teams is another indication Hilliard could end up sticking on the depth chart behind Adrian Peterson and Toby Gerhart.

Coach Leslie Frazier supported that notion on Friday, pointing out Hilliard has far more experience -- he played in all 48 games over the past three seasons with Miami, mostly on special teams -- than Todman, who has yet to appear in a regular-season NFL game.

"Lex has played in this league and been successful, and one of his fortes is being a good special teams player," Frazier said. "So, he's a proven commodity in that area.

"That's one of the reasons we signed him -- because he not only gives you something in the backfield, but he's been a very good special teams player, whereas Jordan has been a guy who was on the practice squad and he's still learning the NFL."

The Dolphins decided not to tender Hilliard, 28, as a restricted free agent in March. The Vikings signed him days later to a one-year, $665,000 deal that included a $25,000 roster bonus and $25,000 workout bonus.

At 5-11 and 235 pounds, Hilliard is built in the Gerhart mold and has a similar, physical running style between the tackles. The Montana product has only 39 career carries for 130 yards (3.3 average) and 26 receptions for 210 yards (8.1) -- most of that production coming in 2009, his first full season after spending 2008 on the practice squad.

Like Hilliard, Todman (5-10, 198) was a sixth-round draft pick (183rd overall out of Connecticut in 2011) and didn't see the field as a rookie. The Chargers waived the 22-year-old on Oct. 22 and re-signed him to their practice squad, where Todman stayed until the Vikings signed him to a three-year minimum deal on Dec. 28.

He's a speed threat who "has some juice," Frazier said, "and that was one of the attractions when we signed him. They are different in their careers and where they are."

The Vikings may be reluctant to keep the less experienced player because Peterson is coming off major knee surgery and remains uncertain for the opener. Frazier has spoken previously about finding a third back who can play every down -- not just in passing situations, as Lorenzo Booker did in that role last season.

Todman also must now overcome the ankle sprain he suffered in Thursday's practice. Frazier said the injury is "just a typical sprain and (Todman) shouldn't be out very many days. Nothing major at all."

The only other halfback on the roster is Derrick Coleman, the undrafted rookie from UCLA who signed for $5,000 in May. Fullback Matt Asiata, in his second camp with the Vikings, also has gotten some carries.

No more live

There will be no live tackling in the annual night practice inside Blakeslee Stadium on Saturday -- or any other time before the Vikings take the field for next Friday's preseason opener at San Francisco.

"It will be more 'thud,'" Frazier said. "(Thursday), I told our guys that the scrimmage we had in short yardage and goal line was our last live situation we'll have before we scrimmage next Friday. We'll still be live on the line, but we just won't take the backs down (Saturday) night."

That probably will be welcome news to veterans -- including right end Jared Allen, who is open about his distaste for training camp and said on Friday this is the toughest one he's seen since he played under Dick Vermeil in Kansas City in 2004 and '05.

The Vikings will be in pads for a sixth consecutive day on Saturday. Multiple sessions so far have pushed 2½ hours.

"I'm surprised about how we've been going live," Allen said. "I tell you what, other than Coach Vermeil, this is the toughest camp I have been a part of. You know, five straight days of pads and we've had live periods in almost every day. So, that was a bit surprising, and that we are here for three weeks."

Unlike in recent years, the Vikings will return for another four days of camp after the exhibition opener. Camp breaks on Aug. 16.

Walsh keeps cooking

There's a long way to go, but rookie place-kicker Blair Walsh has passed every test the Vikings have thrown at him so far.

On Friday, he ran onto the field to hit a 43-yard field goal in a final-play scenario. Then, he ended practice by splitting the uprights from 55 yards.

Walsh, a sixth-round pick out of Georgia, is now 17-of-18 on field-goal attempts in team (11-on-11) drills in camp.

Going nowhere

The first- and second-team offenses each failed in their first shot of this camp at a 2-minute drill, beginning with 1:30 on the clock, two timeouts, the ball at their own 25-yard line and a touchdown deficit.

Christian Ponder was 7-of-10 passing (including a clock-stopping spike) with the starters, but none of the completions gained more than 6 yards and the offense stalled at the 50.

Joe Webb was more efficient with the second string, going 5-of-9 with strikes of 30 yards to Stephen Burton and 14 yards to Devin Aromashodu. But his final throw to the end zone sailed high as time expired, leaving the offense 17 yards short of a tying score.

• Allen, RT Phil Loadholt and special-teams coordinator Mike Priefer were scheduled to speak to about 500 Minnesota-based military personnel who served in Iraq and Afghanistan on Saturday morning as part of a "Beyond the Yellow Ribbon" program.

• Stephen Burton, who opened camp on the active/non-football injury list, had a solid day that also included catching a deep ball in 7-on-7.